The 1979 Islamic Revolution was a nationwide uprising against the dictatorial rule of US-backed Mohammad Reza Pahlavi.
Facing mounting unrest and unable to control the situation, the deposed Shah Mohammad Reza Pahlavi left Iran on 16 January 1979, on a vacation as he said, to never return.
The departure marked the collapse of his authority and left a caretaker government under then Prime Minister Shapour Bakhtiar, the last Prime Minister under Shahs rule.